Motor compressor



1935- R. PATERAS PEscARA 2 MOTOR COMPRESSOR Filed Jan. 5, 1935 2 Sheets-Sheet 1 INVENTOR Raul Dgteras Descara 24, 1935. R. PATERAS PESCARA 2,025,176

MOTCR COMPRESSOR Filed Jan. 5, 1933 2 Sheets-Sheet 2 INVIZNTOR Raul Dateras Descara BY II I 9 Patented Dec. 24, 1935 UNITED STATES PATENT OFFICE MOTOR COMPRESSOR Raul Pateras Pescara, Paris, France Application 5 Claims.

the fuel is injected and in which it is subsequently ignited, the whole working on the two stroke principle. The outer ends of the pistons reciprocate in two compression cylinders respectively disposed on opposite sides of said motor cylinder and coaxially therewith. -The return stroke of the pistons is produced by the expansion of the air cushions that remain in the clearance spaces of said cylinders at the end of the outstroke.

The chief object of the present invention is to provide a motor compressor of that type in which compression of the air for the scavenging of the motor cylinder takes place during the whole of the compression stroke of the pistons.

According to my invention, that result is obtained by providing the pistons with laterally projecting elements adapted to slide in lateral chambers provided in the casing of the coinpressor, said sliding elements acting as pistons in said chambers which are always in communication with the scavenging air reservoir.

This, and other objects of the present invention, will be better understood from the following description of a preferred embodiment of my invention, with reference to the accompanying drawings, given merely by way of example, and in which: I

Fig. 1 is an elevational view, partly in section, of a motor compressor according to the present invention;

Fig. 2 is a horizontal axial section of said com- Dr sser;

Fig. 3 is a composite view, -the right hand side of which is a section on the line AB of Fig. '1, and the left hand side of which is a section on the line CD of Fig. 1;

Fig. 4 is a diagram illustrating the operation of the compressor;

Fig. 5 is an elevational view, partly in section, of a complete compressing unit according to my invention.

In the embodiment shown in the drawings, all the stationary parts of the motor compressor form a unit I in which the following parts are included:

(41) Three cylinders (compression cylinder IOI provided with longitudinal slots I I and connected with delivery pipe I05 through outlet valves not January 5, 1933, Serial No. 650,349 In mince July 5, 1932 shown in the drawings, motor cylinder I02, the ends of which are provided with cooling fins 24 and with a piece 25 screwed thereon and fitted with packing rings 26, and a second compression cylinder, similar to cylinder NH, and which is shown in Fig. 5);

(b) A chamber 2I carried by each compression cylinder, connected with the atmosphere through openings provided with air inlet valves I9, and

connected with the inside of the compression cyl- 10 inder through port 22;

(c) A casing I04 inclosing a chamber I2 extending along the whole length of the compressor and connected with motor cylinder I02 through ports I I;

(d) A chamberJS carried by each compression cylinder IOI, connected with the inside of said cylinder through ports 30 and with chamber l2 through ports I6 provided with valves I'l;

(e) Two longitudinal external recesses provided on either side of said casing I04. closed on the outer side by plates 9, and connected with chamber I5 through ports l8; said recesses are disposed along grooves of compression cylinder IOI.

Two pistons, such as 2, are fitted in said cylinders in such manner that their outer ends reciprocate in the compression cylinders respwtively and their inner ends (of reduced section) reciprocate in motor cylinder I02. The inner faces of the enlarged ends of the pistons are provided with an annular recess 21 for receiving the end of the motor cylinder.

The pistons are connected together through rods 3 pivoted at one end about journals] provided on the pistons, and at the other end to cranks 5 pivoted about journals 6 fitted in unit I.

Journals 4 also carry sliding members 1 adapted to reciprocate in a piston like manner in guiding recesses 8. The inner face of said sliding members is provided with a plate I0 adapted to cover the portion of groove I I located between said journal 4 and the inner end of said groove.

The operation of the apparatus will be better understood by referring to the diagram of 'Fig. 4 in which the pressures in one of the compression chambers are plotted in ordinates and the displacements of the corresponding piston are plotted in abscissas.

The piston starts from its innermost position corresponding to point M of the diagram. It compresses air until it reaches a position corresponding to point N of the diagram, for which valves I I open, thus connecting scavenging air reservoir I2 with compression cylinder IM through ports 30, chamber is, and port It. From N to O, the piston drives compressed air into the scavenging air reservoir. When the piston reaches a position corresponding to'point 0, it closes ports I l and 30 so that thereis no longer any connection between the compressed air in the cylinder and chamber It. From to P, piston 2 compresses air into the compression cylinder IIII. At point K, that is when the pressure in cylinder HH begins to grow very high, piston 2 covers port 22 so that there is no longer any connection between cylinder llli and chamber 2|. When piston 2 reaches a position corresponding to point P, the outlet valves (not shown in the drawings) open and from P to Q air is delivered into outlet pipe I05 at a constant pressure. When piston 2 is in a position corresponding to point Q, said outlet valves are closed. From Q to R, during the first part oi! the instroke, the cushion of compressed air. remaining in the clearance space of the cylinder expands down to the atmospheric pressure. When piston 2 reaches a position corresponding to point R'it uncovers port 22 and valves is open. From R to M, the air from the outside enters into the compression cylinders through said inlet valves and ports 22.

The essential feature of the present invention is that, during the whole of the outstroke of piston 2 auxiliary pistons I compress air in chambers 8, which are always in-communication with scavenging air reservoir l2 through ports l8 and I6, said pistons I continuing their compressing action even when pistons 2 have covered ports H, which increases the amount of air delivered to the scavenging air reservoir and the pressure of said air.

Plates Ill, which are carried by said pistons I, serve to prevent the lubricating oil, which is abundantly supplied to the guiding recesses 8 and to the connecting rods, to mix with the lubricating oil of pistons 2, which may be reduced to a minimum, owing to the absence of any pressure on the walls of the cylinder.

While I have described what I deem to be a practical and efllcient embodiment of my inven-. tion, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form oi! the parts without departing from the principle of my invention as comprehended within the scope of the appended claims.

What I claim is:

1. In a motor compressor including a motor cylinder, two compression cylinders disposed on opposite ends thereof and coaxially therewith, two opposed pistons the inner ends of both or which reciprocate in the motor cylinder and the outer ends or which reciprocate in the compression cylinders respectively, the combination 0! a reservoir tor the compressed air for scavenging the motor cylinder, an auxiliary cylinder fixed on one side of each compression cylinder and connested-to saidraervoir,-auxiliarypistons,.operatively connected with the first mentioned pistons, fitted in said auxiliary cylinders, so as to compress air therein during the whole of the out stroke of the first mentioned pistons, and articulated means for synchronizing the movements of the opposed pistons, said articulated means bein operatively connected with said auxiliary pistons. 5 2. In a motor compressor including a motor cylinder, twocompression cylinders disposed on opposite ends thereof and. coaxially therewith, and two opposed pistons the inner ends of both of which reciprocate in the motor cylinder and the i0 outer ends oil which reciprocate in the compression cylinders respectively, the combination of a reservoir for the compressed air for scavenging the motor cylinder, an auxiliary cylinder fixed on one side of each compression cylinder in parallel relation therewith and connected to said reservoir, auxiliary pistons adapted to reciprocate in said auxiliary cylinders, said compression and auxiliary cylinders being provided with slots parallel to their axes, pins rigidly fixed to said first mentioned pistons and extending through said slots so as to drive said auxiliary pistons, whereby air is compressed in the auxiliary cylinders during the whole of the outstroke of the first mentioned pistons, and articulated means for synchronizing the movement of the opposed pistons, said articulated means being operatively connected with said auxiliary pistons.

3. In a motor compressor including a motor cylinder, two compression cylinders disposed on opposite ends thereof and coaxially therewith, and two opposed pistons the inner ends of both of which reciprocate in the motor cylinder and the outer ends of which reciprocate in the compression cylinders respectively, the combination of a reservoir for the compressed air for scavenging the motor cylinder, a port in each of said compres-sion cylinders for connecting it with said reservoir, at least onetcheck valve for connecting said port with said reservoir so that compressed air is allowed to flow from said port into said reservoir, an auxiliary cylinder fixed on one side 0! each of said compression cylinders in parallel relation therewith and permanently connected with said reservoir, auxiliary pistons, operatively connected with the first mentioned pistons, fitted in said auxiliary cylinders so as to compress air therein during the whole or the outstroke oi the first mentioned pistons, opposed cranks pivoted to the motor cylinder, and connecting rods articuso lat'ed at one end to said cranks and at their other ends to said auxiliaryipistons. I

4. In a device according to claim 2, such slots, ending atpoints spaced from the closed ends of the compression cylinders by such distances that the slots are cut on from the compression cylinders by the pistons before the pistons reach the limits of their strokes. 5. In a device according to claim 2? a"'plate secured to each oi said auxiliary pistons opposite to to and covering at least parts oi! the portions oi the slots between the working faces of the auxilpistons andthe innenends oi the slots..

RAUL rwrmuis PESCARA. u 

